/************************************************************************
 * Copyright (c) 1990, 1993
 *    The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 ************************************************************************/


#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fdopen.c    8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
//#include <sys/cdefs.h>
//__FBSDID("$FreeBSD$");

//#include "namespace.h"
//#include <sys/types.h>
#include "fcntl.h"
#include "unistd.h"
#include "stdio.h"
#include "errno.h"
#include "limits.h"
//#include "un-namespace.h"
#include "local.h"

FILE *
fdopen(int fd, const char *mode)
{
    FILE *fp;
    int flags, oflags, fdflags, tmp;

    /*
     * File descriptors are a full int, but _file is only a short.
     * If we get a valid file descriptor that is greater than
     * SHRT_MAX, then the fd will get sign-extended into an
     * invalid file descriptor.  Handle this case by failing the
     * open.
     */
    if (fd > SHRT_MAX) {
        errno = EMFILE;
        return ((FILE *)NULL);
    }

    if ((flags = __sflags(mode, &oflags)) == 0)
        return ((FILE *)NULL);

    /* Make sure the mode the user wants is a subset of the actual mode. */
    if ((fdflags = fcntl(fd, F_GETFL, 0)) < 0)
        return ((FILE *)NULL);
    tmp = fdflags & O_ACCMODE;
    if (tmp != O_RDWR && (tmp != (oflags & O_ACCMODE))) {
        errno = EINVAL;
        return ((FILE *)NULL);
    }

    if ((fp = __sfp()) == NULL)
        return ((FILE *)NULL);

    if ((oflags & O_CLOEXEC) && fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) {
        fp->_flags = 0;
        return ((FILE *)NULL);
    }

    fp->_flags = flags;
    /*
     * If opened for appending, but underlying descriptor does not have
     * O_APPEND bit set, assert __SAPP so that __swrite() caller
     * will _sseek() to the end before write.
     */
    if ((oflags & O_APPEND) && !(fdflags & O_APPEND))
        fp->_flags |= __SAPP;
    fp->_file = fd;
    fp->_cookie = fp;
    fp->_read = __sread;
    fp->_write = __swrite;
    fp->_seek = __sseek;
    fp->_close = __sclose;
    return (fp);
}
